\documentclass{standalone}
\usepackage{tikz}
\usepackage{ctex,siunitx}
\setCJKmainfont{Noto Serif CJK SC}
\usepackage{tkz-euclide}
\usepackage{amsmath}
\usepackage{wasysym}
\usetikzlibrary{patterns, calc}
\usetikzlibrary {decorations.pathmorphing, decorations.pathreplacing, decorations.shapes,}
\begin{document}
\small
\begin{tikzpicture}[>=latex,scale=0.8]
  \fill [cyan!40] (-3.5,-2.0) rectangle (3.5,0);
  \draw (-3.5,0)--(3.5,0);
  \node at (3,.5){空气};
  \node at (3,-.5){玻璃};
  \draw [thin,densely dashdotted](0,-1.6)node[right]{$N'$}--(0,1.6)node[right]{$N$};	
  \draw[semithick,postaction={decorate},decoration={markings,mark={between positions 0.25 and 0.75 step 0.5 with {\arrow{>}}}}] (150:3.5)node[left]{$A$}--(0,0)--(-45:2.5)node[right]{$B$}; 
  % \draw[->, very thick] (0,0)--(-45:1.5);
  % \draw[>-, very thick](150:1.5)-- (0,0); \draw[very thick] (0,0)--(150:3.5)node[right]{$A$};
  \draw (0,.5) arc (90:150:.5)node[midway,above]{$i$};	
  \draw (0,-.5) arc (-90:-45:.5)node[midway,below]{$r$};		
  \node at (.25,.25){$O$};
\end{tikzpicture}
\end{document}